KnightWarrior

Anybody do this install? I ordered one and plan on putting it on my Z-28's rebuilt 305 (310). It already has 1-3/4 SLP headers and a 3" exhaust. I'm wondering what fuel pump (mechanical) to use and what kind of regulator. Also how big of a hole the hood will need. Will it just be the carb poking up out of the hood or upper half of the blower?
Any info would be great, thanks.

luke4907

iTrader: (5)

I'd post this in the Power Adder forum or check the Aftermarket Product review section to see if anyone already did this.

Apeiron

Weiand has a smog legal blower for thirdgen applications?

KnightWarrior

Yes they do! SummitRacing sells it. Part # WND-6502. It carries a CARB E.O. #D-256-2 for use in California on Chevy small blocks 1969-1985. It retains the smog crap and the EGR!! You even keep the Quadrajet.
They claim gains of 25 to 40% more horsepower!

Apeiron

Interesting, I'd thought that it was just for trucks.

RWB____s

For some reason I just can't imagine a CC Q-jet seting on a roots type blower. I wonder how you tune the carb for the blower application.

Apeiron

The same way you'd tune any other carb for a blower application I suppose.

KnightWarrior

Richer metering rods for the secondaries, otherwise it remains stock.

Damon

Knight's right- the carb still has air drawn though it just like a stock application, so the tune doesn't need to be much different in the carb. The (Qjet) carb on my 142-blown Malibu is using almost the exact same tune as it did on top of the previous N/A 383 motor.

A CC-Qjet will work just fine on it, as long as the rest of the critical computer controlled systems remain functional- VAC sensor, temp sensor, O2, EGR system, etc.

Remember to budget for a new hood becuase the 142 absolutely will not be able to fit under a stock 3rd gen hood. THey call them "underhood blowers" but what they should really be called is "under a big cowl induction hood blowers."

KnightWarrior

Damon, finally. You are da man!! Your article inspired me to do this lunacy! LOL!! I'm actually going to leave the carb exposed with a snazzy STREET SCOOP aircleaner with red butterflys that open with the carb linkage.
What did you do with your fuel pump? Add a regulator?

RWB____s

How about under boost, when more air is being forced into the engine? If your richin the carb, you may run afoul of the factory computer and thro a code. I don't know of any aftermarket chips that will work with a blower/carb setup. You may have to find someone to make a custom chip. That may be difficult now days because everyone is more FI oriented. The software may not work the same for a carb/blower setup. I would be concerned with that.
When I had my H.O. 305 (back in the 80's)I ran a Hypertech chip. It only mildly changed the tune on the engine. Now your dealing with boost and making wholesale changes in the engine setup. I personally don't think that the factory ECM is going to like it.
Good Luck tho. hope you find a way

Damon

The stock programming will work fine. Remember that carbs are, by their nature, 80% "self-compensating" for changes in airflow- the ECM just kinda "trims" the fuel delivery a little to keep it at stoich for idle and part throttle. No chip change required.

For a little stock 305 with this blower a stock fuel system is adequate if it's in good condition. I mean you're going to be going from about 200HP to maybe 300HP, which is well within the capabilities of a stock fuel pump and lines.

KnightWarrior

It sounds like the stock fuel pump will work fine according to two people who have done this conversion. Thanks for the feedback everyone. I'll post pics when it's finished!

Apeiron

When you're under boost, the computer won't be controlling anything but the timing anyway.

Tom 400 CFI

What a disaster that post was....

RWB____s

.

RWB____s

Disaster? whatever. Just commented on a thought. I hope it works for him. Still have a hard time picturing a blower with a CC Q-jet and all this crap on it

KnightWarrior

Ah c'mon that's just a few vacuum lines, air injection tubes and various sensors. It will be easy, just have to add a few more inches of tubing and wire here and there and route everything neatly away from moving parts.
As long as everything is retained it will be just fine. CARB wouldn't issue an EO order # if it wasn't going to work.

RWB____s

Well good luck I never said it wasn't smog legal. If you look close at that picture, thats a CC "holley" carb with a performer manifold on the engine. I purchased it to replace the CC Q-jet. It worked real well and was able to change jets and P/valves as needed for tuning. Passed smog to. Have fun with your project

Damon

It's do-able. I did it with a cc-QJet engine many years ago- using what is basically still the same 142 kit they offer today. We ran the standard "long nose" version of the kit (not the emissions-legal "super-long-nose) since we weren't looking to pass a visual and the car just had a standard 3 v-belt accessory system- no serpentine belts, no smog pump. We did NOT run EGR (the standard 142 kit does not have EGR provisions) or any other emissions equipment but we kept the carb and distributor under the control of the stock ECM and it worked just fine. I believe it was an LG-4 engine, but it's been more than 10 years since I worked on it and it wasn't my car.

I recall we ended up using only the CTS sensor (relocated), the VAC sensor (still attached to it's usual port on the carb), the O2 sensor still in the exhaust and, of course, all the other sensors and such that are contained in the stock computer controlled carb and distributor.

It didn't even look all that cluttered under the hood. With all the emissions stuff on it, yes, it'll look like a nightmare. But as long as everything is hooked up where it needs to be, it'll work.

KnightWarrior

Even with a B hanger and DR rods for the secondaries the computer should still be happy, cause it stops caring about anything but timing at WIDE OPEN THROTTLE. Partial throttle should be just as before. The blower lobes should even help atomize fuel.

Red Devil

That looks promising. Keep us posted.